968927 - Novel Bio-Physicochemical Arsenic Removing Membrane, Combining Organic Arsenic Compounds on Foul Media (Student Poster 14)

For decades, solar panels have been made of CdTe solar cells which contained copper and chlorine, but without these elements reacting together the cells do not perform well. However, a new approach needed to be found since copper can move within the solar cells while in extended use causing the lifespan to shorten because the efficiency changed. Therefore, researchers at the National Renewable Energy Laboratory (NREL) and First Solar removed the copper and replaced it with elements from Group 5 of the periodic table including arsenic. However, the inorganic compounds formed from the chemical combination of arsenic with other atoms can cause many health problems from short and long-term exposure; therefore, the liquid waste from the solar panels manufacturing industries has the potential to cause serious environmental and health problems. To understand how harmful the exposure can be to humans, the limit for arsenic levels in drinking water was issued to 0.01 mg/L by the United States Environmental Protection Agency (US EPA). In order to solve this concern, this project investigated the productivity of two compositions of a novel membrane to remove arsenic from water. The composition of these membranes included: acid-treated etched corn husk, amide, and iron oxide. The membranes were placed over a layer of anthracite, inside two acrylic-contaminated raw water samples, at varying pH levels. The membranes were conveyed, by gravity flow, over two pre-treated, measured, and assembled membranes. The pre-treatment included the following procedures: (i) immersing 10 mg of corn husk in 10 mg of a 1 M solution of hydrochloric acid, then, etching and layering with amide-mixed with iron oxide; and (ii) immersing 10 mg of corn husk in 10 mg of a 10 M solution hydrochloric acid, then, etching and layering with amide-mixed with iron oxide. The results showed both ratios of pretreated cornhusk membranes gave equivalent results. The maximum removal efficacy was observed when the raw water pH was set at 3. Nearly 99% of the removal efficiency was achieved when the initial arsenic level was 15 mg/L. The lab experiments were run at room temperature.